Profiling control mechanism



June 29, 1954 Filed Oct. 18, 1952 E. G. ROEHM PROFILING CONTROL MECHANISM 2 Sheets-Sheet 2 INVENTOR. .Zzwwifiazauv z'ff/m m viz/ 4 ATTORIVIYI Patented June 29; 1954 UNITED STATES PATENT OFFICE Claims.

This invention relates to improvements in milling machine control mechanism and has particular reference to mechanism for use in connection with profiling or contouring machines.

One of the objects of the present invention is the provision of an improved simplified construction for accurate determination of the relative rates of movement of a pair of slide members of such a machine.

A further object of the invention is the provision of a simplified form of control mechanism which may be readily accurately manufactured and assembled and will minimize the overall space requirements as contrasted with prior known commercial constructions.

An additional object of the invention is the provision of an improved simplified and highly accurate adjusting mechanism for determining the relative positioning of the rate and direction control members of a profiling machine.

Other objects and advantages of the present invention should be readily apparent by reference to the following specification, considered in conjunction with the accompanying drawings forming a part thereof, and it is to be understood that any modifications may be made in the exact structural details there shown and described, within the scope of the appended claims, without departing from or exceeding the spirit of the invention.

Figure 1 is a diagrammatic view of a hydraulic machine transmission embodying the present invention.

Figure 2 is an enlarged sectional view through the tracer and rate control mechanism.

Figure 3 is a transverse section on the line 3-3 of Figure 2.

Figure 4 is a section through the adjusting mechanism for the rate determining sleeve shown in Figure 2.

In Figure l of the drawings, the numeral [0 designates a fragmentary portion of the bed of a contour milling machine supporting the longitudinally movable column I2 on which is mounted the transversely adjustable slide l3. Suitable gearing l4, driven by the hydraulic motor I5, reacts against racks [6 on the bed for effecting longitudinal movement of the column 12. Correspondingly, the hydraulic motor I! carried by slide l 3 is provided with a pinion at l8 cooperating with the rack IS on the column for effecting the transverse movement of the slide I3 relative to the column and bed. The hydraulic medium for actuation of these motors is furnished by a pump 20 supplied from reservoir 2| to force the actuating medium under suitable operating pressure through the forward pressure conduit system 22. This system has the branch 22a extending to groove 23 of tracer valve bushing 24 which contains the tracer valve 25 actuated in one direction by spring 26 and in the opposite direction by engagement between the cone 2'! at the lower end of the valve and the collar 28 shiftable by movements of the tracer valve stem 29 under control of tracer finger 30. Defiections of the tracer will move the valve to couple either conduit 21' or conduit 28 to the pressure conduit 22a, while the opposite conduit will be connected by the branches 3 la, 3|b to the return or exhaust conduit 3 I.

The conduits 21' and 28 are connected by way of the short circuiting valve 32 and reversing valve 33 to opposite ports of the rotary hydraulic motor 34. Consequently, on any deflection of tracer finger 3i! shifting the valve 25 from the hydraulic.

neutral position shown in Figure 1 the hydraulic motor will be operated in one direction or the other. The motor is carried by the tracer head frame 38 supported on the cross slide [3.

Motor 34 carries pinion 35 meshing with bevel gear 36 on shaft 31, which is journaled in frame 38, preferably by anti-friction bearings such as 39 and All. The gear 36 is provided with a spur gear portion 4| meshing with gear 42 on sleeve 43 having at its lower end the socket 44 to receive the ball mounting 45 for the tracer sleeve 29.

The upper end of the sleeve slidably supports the tracer valve shift collar 28 actuable by the ball 46 on the upper end of sleeve 29.

By the construction illustrated, the tracer supporting sleeve 43 is rotated in synchronism with the shaft 31. Extending transversely of the shaft 31 is the pivot pin 4! shown in Figure 3 engaged in the ears 48 of the oscillatable frame 49 supporting the thrust ring 50 on the anti-friction mounting 5|. The frame 49 has a dependent flange 52 and is formed with a central clearance aperture 53 to permit of rocking of the frame with respect to the shaft 31 about the pivot pin 4'1.

Additionally, the frame is provided with the cylindrical bore at 54 formed in part in the body of the frame and in part in the depending flange extension. This bore is disposed at an angle to the body of the frame and the plane of the surface of the ring 50. Slidably mounted on the shaft 31, while held for rotation with the shaft as by the key or spline 55, is the adjusting sleeve 56. This sleeve is provided at its lower end with a shifter yoke engaging groove 51 and at its upper end with an adjusting head in the form of a truncation or central section of a sphere angularly disposed with respect to the axis of the sleeve 56. The

diameter of the sphere is such that it has close interfitting engagement with the wall of the bore 54. Suitable means are provided for effecting accurate longitudinal adjustment of the sleeve 5'6 with respect to the shaft 31. As shown in Figure 4, these comprise the shifter pin 60 carried by slide 6| supported for movement, parallel to the axis of shaft 37, by the tracer head casing 38. A spindle 62 journaled in the frame has on one end a pinion G3 meshing with rack 64 on the slide, and on the opposite end the knob or handle 65 for rotating the pinion to effect the accurate adjustment of the slide.

By comparison of Figures 1 and 2 it will be evident that as the sleeve 56 is moved upwardly from the position shown in Figure 1 where the left hand side of frame 49 is depressed, to the position shown in Figure 2 where the thrust ring 50 is level, that the member 49 will be angularly adjusted about its pivot by the inter-engaged sliding relationship of the ball section 58 relative to the wall of the bore 54. Continued upward movement will cause a tilting of the member 49 in the opposite direction to that indicated in Figure 1, but due to the interfitting relationship of the periphery of the ball with the bore 54, the member 49 will be securely held at any angular positional adjustment.

Mounted on the tracer head casing 38 are the valve bushing elements 66 and 6'! which may be 2 produced either as completely separate units as shown in Figure 2, or as a general valve block 68 as indicated in Figure 1. Guided in the valve bushings are the rate and direction control valves 69 and '50 having respectively the valve rods or 1" tips H and 72 preferably rounded at the ends as indicated at 13. As shown in Figure 3, these rods are located at 90 degree spaced points in position such that their tips will ride on the trust ring 56, while the valves and rods are urged in the direction of the thrust ring by the springs Hi and 15.

It will be particularly noted by reference to Figure 2 that the relationship between the axis of the pivot pin 41 and the surface of the thrust ring 58 is such that the surface in question is disposed an appreciable amount below the axis. Likewise, the ends or tips of the rods H and 12 are rounded about radii corresponding to the amount of this offsetting of the surface 59 with d respect to the axis of 41. By this construction with the parts in the position shown in the drawings, that is, with the rod '12 contacting ring 58 at a point in an axial plane with the pivot 41 the vertical position of the valve stem or rod (2 will be unchanged by any rocking movement of ring 5!) and neither raised nor lowered by such angular adjustment, which effect might take place if the axis of pivot 41 lay in the plane of the surface of ring 50, due to the varying point of engagement of the end of the rod and the ring.

As shown in Figure 1, the pressure conduit system 22 has a branch 22b extending to groove 16 of the bushing or guide for the valve 69 and connected by way of conduit 11 to the groove 18 of the guide for the valve 10. The valve and its stem 12 extend with their axes parallel to but offset with respect to the axis of the shaft 37,

and the relationship between the surface of the thrust ring or annular abutment and the end of rod 72 is such that when the pivot l! is disposed perpendicular to the axis of rod 12, the central spool '19 of valve 10 will be in a neutral position, either sealing the fiow of pressure medium or balancing the pressure in the conduits and 8| which extend from the valve bushing or casing to the motor ll. Displacement of the spool 79 from its neutral or centralized position in either direction will couple the pressure to one or the other of the conduits 86 or BI, and at the same time connect the non-pressure conduit with the exhaust grooves 82, 83 connected by way of the passages $4, 85 to exhaust grooves -86, 81 and thus to the exhaust or back pressure conduit am.

If the member 49 is in the level or non-tilted position indicated in Figure 2, the valve stem H and valve 59 also will be held in a neutral position. If, however, this member is tilted, as shown in Figure l, at the time the valve spool is is held in its central or neutral position the central spool 88 of valve 69 will have been moved downward by spring l-l, connecting the pressure conduit 22b with the motor conduit 89 extending to one side of the motor l5, while the conduit 90 from the opposite side of the motor will be connected to the exhaust conduit 3m, causing activation of the motor 15 to effect longitudinal movement of the column l2 on the bed IO. In this position of the parts, movement will be effected solely by the column I2 in a longitudinal direction, the cross slide I3 remaining stationary with respect to the column. However, upon pattern effected deflection of the tracer finger 30 by engagement with a rise or fall in the contour of the pattern ill, the tracer valve will be moved causing an activation of motor 34 and a corresponding rotation of shaft 31. As this takes place, considering for the moment a clockwise rotation of the shaft as viewed in Figure 3, the valve 69 will rise as the tip 13 rides upward on the abutment surface of 50 while the tip of the valve rod or stem 12 will tend to move downward. This will reduce the rate of actuation of the column motor [5 and initiate actuation of the cross slide m0- tor ll. These equal and opposite movements of the valve members will continue throughout a quarter of a revolution of shaft 31. During the 5 next quarter of a revolution the spool 19 will be moved toward a closed position to slow down the cross slide movement while the spool 88 will be moved upward relative to the groove .15 to effect actuation of the column in the opposite direction. It will be understood that the tracer unit assembly 38 is carried by the slide 13, as is the cutter spindle unit 93. They are thus shifted together in an ambulatory path corresponding to the vectorial resultant of the individual paths of the respective slides.

Ordinarily, the tracer finger 38 is slightly-offset with respect to the axis of rotation of the tracer sleeve 29 in an anticipatory direction so that on slight deflection, causing shifting of the valve 25 and energization of the motor 34, the rotation of sleeve 43 will move the tracer toward oraway from the pattern in an arcuate path in a manner to compensate quickly for such deflection so that the rotary movement of shaft 3'! and sleeve 4:3 are very accurately controlled. Upon any movement, however, of the shaft 37, the members d9-E5B will react variably to position the respective valves 69 and 7D to vary the vectorial component direction of bodily movement of the tracer and cutter units. The disposition of the valves 69 and iii in a position parallel with each other and with the shaft 3'! facilitates manufacture and assembly of the parts and location within a relatively limited space area with a common direction of reaction of the two valve stems against the member 50. At the same time the shaping of the contacting ends of the valve rods or stems, together with the anti-friction mounting of the member 59 minimizes frictional resistance to the movement of the cam element with respect to the rods and facilitates accurate control of the automatic adjustment of the parts.

Also, by the pivoted securing of the member 49 to the shaft ill and the employment of the slidably adjustable angularly disposed sphere section on the member 56 cooperating with the cylindrical bore at M in the member 49, extremely accurate minute adjustments may be made of the angle of the member 49 which is determinative of the amount of valve displacement, and thus the maximum rate of actuation of the respective motors l5 and 34 While the parts are Securely held by their interengaged relation in any position of adjustment within the range of the machine.

What is claimed is:

1. A hydraulic control system for a machine tool having a pair of slides movable in angularly related directions, said control including a pair of slide operating hydraulic motors, a source of actuating medium, a pressure conduit system, a pair of parallel valve members, connections between the pressure conduit system and each of said valve members, conduit means interconnecting one of the valves with one of the slide operating hydraulic motors and the other valve to the other of the slide operating hydraulic motors, a shaft rotatably supported adjacent the valve members with its axis extending in a direction parallel with the axes of the valve members but ofiset with respect to the valve axes, a frame member pivoted-to the shaft for rotation therewith and for angular adjustment relative thereto, said frame member including an annular,

abutment portion extending in a direction substantially at right angles to the axis of the shaft, operating rods intervening said abutment portion and the respective valve members, means for variably adjusting the angular relationship of the frame member with respect to the shaft, and means for rotating the shaft variably to position the abutment surface of the member with respect to the contact portions of the valve rods.

2. A hydraulic control system for a machine tool having a pair of slides movable in angularly related directions, said control including a pair of slide operating hydraulic motors, a source of actuating medium, a pressure conduit system, a pair of parallel valve members, connections between the pressure conduit system and each of said valve members, conduit means interconnecting one of the valves with one of the slide operating hydraulic motors and the other valve to the other of the slide operating hydraulic motors, a shaft rotatably supported adjacent the valve members with its axis extending in a direction parallel with the axes of the valve members but offset with respect to the valve axes, a frame member pivoted to the shaft for rotation therewith and for angular adjustment relative thereto, said frame member including an annular abutment portion extending in a direction substantially at right angles to the axis of the shaft, operating rods intervening said abutment portion and the respective valve members, means for variably adjusting the angular relationship of the frame member with respect to the shaft, and means for rotating the shaft variably to position the abutment surface of the member with respect to the contact portions of the valve rods,

6,. said means for rotating the shaft including a rotatable tracer, a gear member carried by the shaft and in driving relation with the rotatable tracer, and a tracer controlled hydraulic motor coupled with the gear member for effecting rotation of the shaft and tracer.

3. A hydraulic control system fora machine tool having a pair of slides movable in angularly related directions, said control including a pair of slide operating hydraulic motors, a source of actuating medium, a pressure conduit system, a pair of parallel valve members, connections between the pressure conduit system and each of said valve members, conduit means interconnecting one of the valves with one of the slide operating hydraulic motors and the other valve to the other of the slide operating hydraulic motors, a shaft rotatably supported adjacent the valve members with its axis extending in a direction parallel with the axes of the valve members but offset with respect to the valve axes, a frame member pivoted to the shaft for rotation therewith and for angular adjustment relative thereto,

said frame member including an annular abutment portion extending in a direction substantially at right angles to the axis of the shaft, operating rods intervening said abutment portion and the respective valve members, means for variably adjusting the angular relationship of the frame member with respect to the shaft, and means for rotating the shaft variably to position the abutment surface of the member with respect to the contact portions of the valve rods, said frame member having a clearance aperture to permit angular adjustment of the frame member with respect to the shaft and having an additional angularly disposed cylindrical bore circumscribing the shaft, and a sleeve slidable on the shaft having a spherically contoured adjusting head angularly disposed with respect to the axis of the sleeve and in close interfitting engagement with the cylindrical bore of the frame member whereby axial sliding movement of the sleeve on the shaft will react through the head on the bore to effect angular adjustment of the frame.

4. A hydraulic control system for a machine tool having a pair of slides movable in angularly related directions, said control including a pair of slide operating hydraulic motors, a source of actuating medium, a pressure conduit system, a pair of parallel valve members, connections between the pressure conduit system and each of said valve members, conduit means interconnecting one of the valves with one of the slide operating hydraulic motors and the other valve to the other of the slide operating hydraulic motors, a shaft rotatably supported adjacent the valve members with its axis extending in a direction parallel with the axes of the valve members but offset with respect to the valve axes, a frame member pivoted to the shaft for rotation therewith and for angular adjustment relative thereto, said frame member including an annular abutment portion extending in a direction substantially at right angles to the axis of the shaft, operating rods intervening said abutment portion and the respective valve members, means for variably adjusting the angular relationship of the frame member with respect to the shaft, means for rotating the shaft variably to position the abutment surface of the member with respect to the contact portions of the valve rods, said frame member having a clearance aperture to permit angular adjustment of the frame member with respect to the shaft and having an additional angularly disposed cylindrical bore circumscribing the shaft, and a sleeve slidable on the shaft having a spherically contoured adjusting head angularly disposed with respect to the axis of the sleeve and in close interfitting engagement with the cylindrical bore of the frame member whereby axial sliding movement of the sleeve on the shaft will react through the head on the bore to effect angular adjustment of the frame, and means for effecting accurate axial adjustment of the sleeve with respect to the shaft.

5. A hydraulic control system for a machine tool having a pair of slides movable in angularly related directions, said control including a pair of slide operating hydraulic motors, a source of actuating medium, a pressure conduit system, a pair of parallel valve members, connections between the pressure conduit system and each of said valve members, conduit means interconnecting one of the valves with one of the slide operating hydraulic motors and the other valve to the other of the slide operating hydraulic motors, a shaft rotatably supported adjacent the valve members with its axis extending in a direction parallel with the axes of the valve members but offset with respect to the valve axes, a frame member pivoted to the shaft for rotation therewith and forangular adjustment relative thereto, said frame member including an annular abutment portion extending in a direction substantially at right angles to the axis of the shaft, operating rods intervening said abutment portion and the respective valve members, means for variably adjusting the angular relationship of the frame member with respect to the shaft, means for rotating the shaft variably to position the abutment surface of the member with respect to the contact portions of the valve rods, said frame member having a clearance aperture to permit angular adjustment of the frame member with respect to the shaft and having an additional angularly disposed cylindrical bore circumscribing the shaft, and a sleeve slidable on the shaft having a spherically contoured adjusting head angularly disposed with respect to the axis of the sleeve and in close interfitting engagement with the cylindrical bore of the frame member whereby axial sliding movement of the sleeve on the shaft will react through the head on the bore to effect angular adjustment of the frame, means for effecting accurate axial adjustment of the sleeve with respect to the shaft, and means keying the sleeve on the shaft to permit axial movement of the sleeve while preventing relative rotation of the sleeve and shaft.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,107,063 Roehm Feb. 1, 1938 2,412,549 Yates et a1. Dec. 10, 1946 2,622,489 Roehm Dec. 23, 1952 

